UK Center for Clinical and Translational Science

Prescription Medication Interactions

Purpose

This study will examine the effects of doses of opioid/placebo and doses of sedative/placebo, alone and in combination. The primary outcomes are related to pharmacodynamic measures (subjective ratings of drug liking and other abuse-related effects; physiological outcomes) to determine the interaction effects of these compounds.

Conditions

Opioid Use
Sedative Use

Eligibility

Eligible Ages: Between 18 Years and 55 Years
Eligible Sex: All
Accepts Healthy Volunteers: No

Inclusion Criteria

Healthy adults, ages 18-55 - Current non-medical use of opioids and sedatives

Exclusion Criteria

Physical dependence on opioids, alcohol, or benzodiazepines/sedatives/hypnotics - Seeking treatment for drug use - Significant medical problems

Study Design

Phase: Phase 1
Study Type: Interventional
Allocation: Randomized
Intervention Model: Crossover Assignment
Primary Purpose: Basic Science
Masking: Double (Participant, Investigator)
Masking Description: This is a randomized, double-blind, double-dummy, placebo- controlled design

Arm Groups

Arm	Description	Assigned Intervention
Placebo Comparator Placebo / Placebo	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Placebo / Oxycodone 20mg	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Placebo / Oxycodone 40mg	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Gabapentin 600mg / Placebo	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Gabapentin 1200mg / Placebo	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Gabapentin 600mg / Oxycodone 20mg	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Gabapentin 1200mg / Oxycodone 20mg	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Gabapentin 600mg / Oxycodone 40mg	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.
Experimental Gabapentin 1200mg / Oxycodone 40mg	Participants will receive non-therapeutic experimental doses of gabapentin (600 and 1200 mg, p.o.), alone and in combination with oxycodone (20 and 40 mg, p.o.). The experimental sessions are designed to capture the time-action curves for the test drugs (Tmax for gabapentin ≈ 2.5 hr; oxycodone ≈ 1.5 hr). Therefore, oxycodone will be administered 1 hr after gabapentin to align peak responses.	Drug: Opioid Agonist Abuse liability evaluation. Drug: Sedatives Abuse liability evaluation.

Recruiting Locations

More Details

NCT ID: NCT04315181
Status: Completed
Sponsor: Sharon Walsh

Detailed Description

Gabapentin and oxycodone are commonly used in combination for the treatment of chronic pain. Gabapentin is now widely misused/abused with studies indicating that gabapentin abuse is especially common among individuals with opioid misuse. The nature of gabapentin's abuse-related effects have been described in case reports and online as sedative-like and opioid-like, with descriptive reports including sedation, euphoria, talkativeness and increased energy. Despite their widespread co-administration both for licit and illicit purposes, no controlled psychopharmacological studies to our knowledge have directly examined the effects of oxycodone (or another opioid agonist) and gabapentin in combination. This study's objective is to characterize the subjective effect profile of gabapentin, examine the interaction between gabapentin and oxycodone, and assess the acute analgesic response to gabapentin and oxycodone, alone and in combination, across a range of doses for each drug.

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.